Whipstocks are well known to the hydrocarbon industry as devices providing a hardened diverter face useful to cause a milling tool run into the downhole environment either behind (single trip) or after (multiple trips) the whipstock to track through a wall of a borehole whether that hole be cased or open. The ability to cause such “side tracks” is important in that it is the basis for multilateral wellbore technology. Multilateral technology has dramatically enhanced the ability of operators to recover hydrocarbon materials from subsurface formations by accessing multiple reservoir areas from a single surface location. This reduces the cost involved with recovering the hydrocarbon materials and in addition, reduces the footprint of a well system at the surface.
Inherent in the milling of either a casing or the formation or both is the production of debris. Debris in the wellbore is undesirable because it tends to cause malfunctions in well equipment resulting in delays and additional costs in running the well operation. In order to avoid debris falling down the wellbore, debris barrier devices have been employed by the industry. Unfortunately, an effective debris barrier has eluded the art.